App Icon doesn't appear in window title bar

[ThanhHaiDang96]

Description

Hi, I'm using MAUI to create an application which's running on Windows and Mac platform.

In my main page, I have a button. And when button is clicked, another window appears.
I set the icon app in .csproj file:

!-- App Icon -->
		<MauiIcon Include="Resources\AppIcon\thumb_logo.svg" ForegroundFile="Resources\AppIcon\thumb_logo.svg" Color="#00FFFFFF" />

However, the icon doesn't appear in title bar in all of windows of this app.

My Button clicked handler:

private void OnCounterClicked(object sender, EventArgs e)
        {
            var win = new Window(new NewPage());

            win.Title = "Secondary Window";

            Application.Current?.OpenWindow(win);
        }

How can I show the icon in window title bar? Specially, in the secondary window.

Steps to Reproduce

1. Create new MAUI App project
2. Change App Icon in .csproj file
3. Add new content page and set name as "New Page"
4. Update OnCounterClicked() in MainPage.xaml.cs file

private void OnCounterClicked(object sender, EventArgs e)
        {
            var win = new Window(new NewPage());

            win.Title = "Secondary Window";

            Application.Current?.OpenWindow(win);
        }

5. Run and Test

Link to public reproduction project repository

No response

Version with bug

8.0.6

Is this a regression from previous behavior?

Yes, this used to work in .NET MAUI

Last version that worked well

Unknown/Other

Affected platforms

iOS, Android, Windows, macOS

Affected platform versions

No response

Did you find any workaround?

Nothing

Relevant log output

No response

[drasticactions]

tl;dr I don't think this is a bug, but it's confusing. This is a bug, read second comment for answer.

As far as I'm aware, for the current version of the TitleBar, it's never supported that. Reading the documentation that field is for the package icon (Used in the start menu, etc), not for a window icon.

By default, WinUI 3 apps look like this.

The default AppWindow bar uses the Windows title bar, which includes an icon. But this icon isn't set by WinUI, even though it includes a package icon

To change it, you would need to set it. However, MAUI doesn't use the default Windows toolbar, it extends the baseline Window into it. This implementation includes an app name, but no icon.

That said,

maui/src/Core/src/Platform/Windows/MauiWinUIWindow.cs

Lines 183 to 200 in a01e1ee

	void SetIcon()
	{
	var processPath = Environment.ProcessPath;
	if (!string.IsNullOrEmpty(processPath))
	{
	var index = IntPtr.Zero; // 0 = first icon in resources
	_windowIcon = ExtractAssociatedIcon(IntPtr.Zero, processPath, ref index);
	if (_windowIcon != IntPtr.Zero)
	{
	var appWindow = AppWindow.GetFromWindowId(Win32Interop.GetWindowIdFromWindow(WindowHandle));
	if (appWindow is not null)
	{
	var iconId = Win32Interop.GetIconIdFromIcon(_windowIcon);
	appWindow.SetIcon(iconId);
	}
	}
	}
	}

They do pinvoke into Win32 and set the AppIcon. But this icon will only appear if you disable the Extended toolbar.

This is not the default behavior, and I don't think there is a MAUI API to do this AFAIK. You would need to know how to access the handler and call that bool yourself. And it would also break any TitleBar customization you have, since it's not the title bar. I would need to look through the history more, but my guess is that for net6.0, MAUI either didn't use ExtendsIntoToolbar and would then show the icon, or it always did and this code wasn't hit unless you knew enough to set it.

But, for the existing titlebar, AFAIK, it doesn't have a way to set that icon yourself. I could be missing something, but I think that would need to be a feature to be added.

@PureWeen what do you think?

[drasticactions]

You see what I just said above? Yeah, I was wrong, this is a bug

maui/src/Core/src/Platform/Windows/Styles/WindowRootViewStyle.xaml

Lines 22 to 29 in a01e1ee

	<Image
	x:Name="AppFontIcon"
	HorizontalAlignment="Left"
	VerticalAlignment="Center"
	Source="Square44x44Logo.png"
	Visibility="{Binding WindowTitleIconVisibility}"
	Width="16"
	Height="16"/>

That's the default template for the titlebar. It's linking to an icon that doesn't exist in the package.

@ThanhHaiDang96 if you go into your Platform/Windows/App.xaml and add the following resource dictionary

    <maui:MauiWinUIApplication.Resources>
        <DataTemplate x:Key="MauiAppTitleBarTemplate">
            <Border
            Canvas.ZIndex="1" 
            VerticalAlignment="Stretch"
            Margin="0,0,0,0">
                <StackPanel Orientation="Horizontal" Margin="12, 0, 0, 0" x:Name="RootStackPanel">
                    <Image 
                    x:Name="AppFontIcon"
                    HorizontalAlignment="Left" 
                    VerticalAlignment="Center"
                    Source="{YOUR APPICON NAME HERE}Logo.png"
                    Visibility="Visible"
                    Width="16" 
                    Height="16"/>
                    <TextBlock 
                    x:Name="AppTitle"
                    VerticalAlignment="Center"
                    Margin="{Binding WindowTitleMargin}"
                    Text="{Binding WindowTitle}"
                    Foreground="{Binding WindowTitleForeground}"
                    Style="{StaticResource CaptionTextBlockStyle}" />
                </StackPanel>
            </Border>
        </DataTemplate>
    </maui:MauiWinUIApplication.Resources>

Replace YOUR APPICON NAME HERE with the name if your icon. If it doesn't work, go into the bin net8.0-windows10.0.19041.0\win10-x64\AppX folder and see what got generated. That should get the icon back.

That's what an extra 5 minutes of searching gets me.

[PureWeen]

Duplicate of #6908

[Foda]

@ThanhHaiDang96 as an alternative, you just need an image with the name square44x44logo in your project:

Ex:
<MauiImage Include="Resources\AppIcons\square44x44logo.svg" />